A chemically amplified resist composition used for semiconductor microfabrication employing a lithography process contains an acid generator comprising a compound generating an acid by irradiation.
In semiconductor microfabrication, it is desirable to form patterns having high resolution and good pattern profile, and it is expected for a chemically amplified resist composition to give such patterns.
U.S. Pat. No. 5,968,713 A discloses a chemically amplified resist composition comprising a resin which comprises a structural unit derived from 2-methyl-2-adamantyl methacrylate.
U.S. Pat. No. 6,239,231 B1 discloses a chemically amplified resist composition comprising a resin which comprises a structural unit derived from 2-alkyl-2-adamantyl methacrylate and a structural unit derived from 3-hydroxy-1-adamantyl acrylate.
US 2005/0100819 A1 discloses a chemically amplified resist composition comprising a resin which comprises a structural unit derived from 2-isopropyl-2-adamantyl methacrylate, a structural unit derived from 3-hydroxy-1-adamantyl acrylate and a structural unit derived from 5-acryloyloxy-2,6-norbornenelactone.
WO 2007/046388 A1 discloses a chemically amplified resist composition comprising a resin which comprises a structural unit derived from 1-ethyl-1-cyclohexyl methacrylate, a structural unit derived from 3-tert-butoxycarbonyloxy-1-adamantyl acrylate and a structural unit derived from α-acryloyloxy-γ-butyrolactone.